THE RAY SPIDER AND HER SNARE. 



201 



have even seen individuals with the back turned downward, Fig. 194, as 

 is the habit with tlie Triangle spider and with all those species who make 

 a dome or horizontal orbweb, as the Basilica spider and the Orchard 

 spider. (See Chapter IX.) 



If now the feet of the spider be carefully examined with a good glass, 

 a coil of slack line will be seen, precisely as in the case of the Triangle 

 spider. This is illustrated at Fig. 194, where a, b, c, are the axes of 

 several rays, grasped in the third (3) and fourth (4) pairs of legs, and SI 

 is the coil or slack line curled up between these and the fore pairs (1 and 

 2), or simply between the pair of fore legs; that is, between the two first 

 and the two second feet. As the spider does not exceed one-eighth of an 

 inch in Ijody length, and the position of the snare is within cavities and 

 interstices of rocks, where the light does not bring out the delicate tracery 

 of the fine webs, the observation of 

 these and other points of like char- 

 acter, is a matter of some difficul- 

 ty. But, although the exact relations 

 of the coil to the feet were some- 

 times in doubt, and indeed seemed 

 to vary somewhat, the existence of 

 the coil and its general relations 

 were determined bej'^ond douljt. It 

 is also certain that the slack line 

 sharply uncoils and straightens when 

 the spider releases her grasp upon 

 the trapline, and that the web un- 

 bends and shoots quickly forward. 

 It is instantly changed from the 



bowed or conical form of Flo's. 190 F"5. 195. Ray spider in position, back upward, sUow- 



, *^'tt ^^^ slack coil and foot basket, ii; axis of a ray 



and 191 to the CU-Cular plane of Figs. grasped by third foot, 3; trapUne grasped by fore 



187 and 188. f««'- 



The following points, however, long evaded my observation, before 

 webs were found whicli presented the conditions for successful study. But 

 at last I was well satisfied. The "springing" of the snare is 

 th S caused by the sudden releasing of the trapline from the fore 



feet, instead of the hind feet, as with the Triangle spider. The 

 polarity of the two arachnids relative to their webs is reversed, Ilyptiotes 

 having her fore feet, but Theridiosoma her hind feet towards the snare. 

 The slack line is therefore coiled between the two fore feet or between the 

 fore and hind feet of Theridiosoma, but between the two hind pairs (as 

 a rule) of Hyptiotes. 



I have already explained the manner in which Hyptiotes is affected 

 when her two hind feet are released from the trapline. The coil straight- 

 ens, and the whole body of the spider shoots forward. If now we turn to 



